Around two weeks ago I lost my ability to hit a two handed backhand. If I try to hit one, one of two things will happen.
1: It ends up all spin and no power and will go around ten mph into the middle of the net
2: If I try not to spin it it will fly randomly with no spin or control and generally go beyond the baseline.
I have no idea how this happened, generally my backhand is a fairly strong shot. One clue I have though is that I don't seem to be using my left arm much. Have any of you had similar problems? How can I drive through the ball to get spin but also power? Should I just rebuild it from scratch?
I'd appreciate any advice you all can give.

On the bright side my slice backhand has gotten around three times better

Around two weeks ago I lost my ability to hit a two handed backhand. If I try to hit one, one of two things will happen.
1: It ends up all spin and no power and will go around ten mph into the middle of the net
2: If I try not to spin it it will fly randomly with no spin or control and generally go beyond the baseline.
I have no idea how this happened, generally my backhand is a fairly strong shot. One clue I have though is that I don't seem to be using my left arm much. Have any of you had similar problems? How can I drive through the ball to get spin but also power? Should I just rebuild it from scratch?
I'd appreciate any advice you all can give.

On the bright side my slice backhand has gotten around three times better